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71.
Summary The four days administration of D-6-methyl-8-[-isopropylaminoethyl]ergoline-I (VÚFB-10726) to nursing rats decreases adenohypophyseal prolactin as determined with disc electrophoresis, and produces changes in the histological appearance of adenohypophyses, which indicate the inhibition of prolaction production and secretion.The authors thank Dr.I. J. Skála, Mrs.J. Boubínová, Mrs.J. Emanuelová and Mrs.V. Maitová for technical assistence.  相似文献   
72.
Summary A side-effect of the administration of cyproterone acetate, an antiandrogenic steroid, to newborn, juvenile or adult male mice (in doses comparable to those used clinically) was found in a marked reduction of the white pulp of the spleen and reduced weight or even absence of the thymus.This investigation received financial support from the World Health Organization.  相似文献   
73.
Pfiester LA  Popovský J 《Nature》1979,279(5712):421-424
SEXUAL reproduction has so far been unknown among the Dinococcales, unicellular brown algae belonging to the Dinophyceae (dinoflagellates). As we report here, however, the life cycles of two members of this group, Stylodinium sphaera and Cystodinedria inermis, include a parasitic amoeboid stage which brings about vegetative reproduction and also possibly sexual reproduction. We believe that the two amoeboid forms have previously been identified mistakenly as a separate taxon of protozoon.  相似文献   
74.
Zusammenfassung DOPA hemmt die Überleitung von Afferenzen des Flexorreflexes zu den primären Afferenzen, Vorderhornzellen und aufsteigenden Bahnen. Es steigert den Flexorreflex, vielleicht dadurch, dass es die Übertragung zu den primären Afferenzen stärker beeinflusst als zu den Vorderhornzellen. Möglicherweise ist eine absteigende Bahn, welche die Übertragung von Flexorreflex-Afferenzen hemmt, noradrenergisch.  相似文献   
75.
Zusammenfassung Die partielle Blockierung der toxischen Effekte von 5-Azacytidin in normalen Mäusen mit Uridin, Cytidin und 6-Azauridin wird beschrieben. Die Hemmung der toxischen Effekte eines Antimetaboliten durch einen anderen kann für die Krebschemotherapie von Bedeutung sein.  相似文献   
76.
Summary The quantity of phyto-estrogens in red clover, hop, peas, and cabbage was estimated by titration on castrated female rats and infantile mice. The level of phytoestrogens was as follows: in hop 1050–2000/kg, in peas 4–6/kg, in cabbage 24/kg, and in red clover 6–9/kg. The author supposes that the sexual disorders described byRosenberger 14 in cows fed with cabbage, can be explained by the presence of phyto-estrogens in this plant.  相似文献   
77.
Spurný P  Oberst J  Heinlein D 《Nature》2003,423(6936):151-153
Photographic observations of meteoroids passing through the atmosphere provide information about the population of interplanetary bodies in the Earth's vicinity in the size range from 0.1 m to several metres. It is extremely rare that any of these meteoroids survives atmospheric entry to be recovered as a meteorite on the ground. Príbram was the first meteorite (an ordinary chondrite) with a photographically determined orbit; it fell on 7 April 1959 (ref. 1). Here we report the fourth meteorite fall to be captured by camera networks. We determined the atmospheric trajectory and pre-atmospheric orbit of the object from the photographic records. One 1.75-kg meteorite--named Neuschwanstein and classified as an enstatite chondrite--was recovered within the predicted impact area. The bolide's heliocentric orbit is exceptional as it is almost identical to the orbit of Príbram, suggesting that we have discovered a 'stream' of meteoritic objects in an Earth-crossing orbit. The chemical classifications and cosmic-ray exposure ages of the two meteorites are quite different, however, which implies a heterogeneous stream.  相似文献   
78.
79.
Summary The substitution of sucrose in the nutrient medium for in vitro pollinated placentae by glucose and fructose favours seed formation and considerably enhances the germination of seeds just attaining maturity. This effect of invert sugar was wholly suppressed in the mixture with two parts of sucrose.  相似文献   
80.
Summary During postnatal development, MAO activity in the thyroid gland of male rats increases until day 16, when adult values are reached.  相似文献   
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